Knife sheath



FIG. 1 is a front and side perspective view of a knife sheath;

FIG. 2 is a front elevation view thereof;

FIG. 3 is a rear elevation view thereof;

FIG. 4 is an enlarged bottom plan view thereof; and,

FIG. 5 is an enlarged top plan view thereof.

The features shown in broken lines represent environmental subject matter that are for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a knife sheath, as shown and described. 